Cod sursa(job #1916215)

Utilizator sebastianciunCiun Sebastian sebastianciun Data 9 martie 2017 08:38:43
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.45 kb
#include <iostream>
#include <cmath>
#include <fstream>
using namespace std;
int n,i,r,a[2000001],j,cnt,x,k;
int main()
{
    ifstream fin("ciur.in");
    ofstream fout("ciur.out");
    fin>>n;
    for(i=2;i<=2000000;i++) a[i]=1;
    for(i=2;i<=2000000;i++)
        if(a[i]==1)
            for(j=2;j*i<=2000000;j++)
                a[i*j]=0;
    for(i=1;i<=n;i++)
    {
        fin>>x;
        if(a[x]==1) cnt++;
    }
    fout<<cnt;
}